"We, as a family, have a renewed faith and a renewed hope that with community efforts, we do expect to find Holly and I do ask everyone to please take a close look at your neighbors," Karen Bobo said today.

Tennessee nursing student Holly Bobo, 20, disappeared April 13, 2011, when a man in camouflage dragged her into the woods near her home in rural Decatur County, about three hours from Nashville. Her brother Clint, 25, saw her go into the woods, but mistakenly believed the man was her boyfriend. There are no suspects in her disappearance.

The events in Cleveland have stirred conflicting emotions among the families of missing persons, ranging from hope to fear, and encouraged advocates that the media attention will inspire families to become the driving force behind the police investigations.

Monica Caison said her phone has been ringing constantly since before 5 a.m. Tuesday with calls from the families of missing persons with whom she has worked.

Caison is the founder and director of the North Carolina-based CUE Center for Missing Persons.

"It's like, 'I'm not crazy. My daughter still could be alive.' And all of those kinds of conversations with other families calling, saying, 'Oh, my gosh, this is amazing. I'm just so happy for these families,'" Caison told ABCNews.com.

"And then there are others that have just been sad and wondering, 'Is it ever going to be my turn?'" she said. "It's been a lot of mixed emotions."

The search for Holly was briefly renewed in April 2012 when authorities found a woman's purse that they believed to be hers near her home. Her family later said they did not believe it was her bag, but have not lost hope.

"We have never stopped looking for Holly," Karen Bobo said. "We have continued to look for Holly and I would hope that law enforcement is doing the same.

Tennessee Bureau of Investigation spokeswoman Kristin Helm said that every case is assigned to an agent and remains an open investigation.

Helm said that there are two different ways that cases like Bobo's continue in the bureau. One way is from leads or tips from the public or if a piece of evidence is found.

"All of those things you take as investigative leads and you follow up on them," Helm told ABCNews.com.

The second way is when investigative leads are developed by the agents themselves, perhaps by taking it upon themselves to re-interview someone, talk to an original witness or pull additional records.

"There's a million different ways an investigation can take twists and turns," Helm said.

"When cases die down and tips die down, that's where the families have to pick up the torch," Caison said. "They have to get out there in the community.

"They have to be out there on the streets, keep putting fliers out, do the billboards, whatever it takes to keep that awareness constantly going to aid their cases back to law enforcement."

She said law enforcement will usually come back to a case when there are tips or activity, whether it's a recent case or a cold case.

"I explain that to families all the time, 'I know you're tired, I know you're stressed out. You don't want to keep on, but you have to keep plugging away because you're going to get another tip and it could be the tip,'" Caison said.